Multicenter study on the treatment of secretory otitis media with ambroxol. Importance of a surface-tension-lowering substance.

Animal studies showed the presence of a surfactant substance in the Eustachian tube. On the premise that alteration of surfactant-like substance might cause pathology of the middle ear in man, a multicenter (24 ENT hospitals) double-blind trial versus placebo was carried out in 435 adults and children with secretory otitis media. Treatment was ambroxol, a drug that changes the bronchial secretions and promotes surfactant synthesis. The dosage regimen was as follows: adults--one 30-mg tablet of ambroxol 3 times/day; children--9 mg of ambroxol syrup, 4 times daily. The treatment lasted 15 days. The clinical signs and symptoms (hypoacusis, conduction deafness) and the otoscopic and rhinoscopic findings of treated patients improved. The differences in these parameters between patients given ambroxol and the controls were statistically significant (p less than 0.05). The symptomatological amelioration was supported by improvement in tympanometric findings and hearing threshold. Drug tolerance was excellent.